Agilent Triple Quadrupole MS and Sensitivity 3
Example of chemical noise reduction
Agilent 6400 Series Triple Quad LC/MS Concepts Guide 43
Example of chemical noise reduction
The Agilent 6400 Series Triple Quadrupole mass spectrometer
passes through four transitional steps in translating a signal in
the MRM process (Figure 18).
Step 1 The spectrum at the far left represents everything that
is being ionized at the ion source. This example shows the ESI
spectrum of a phenylurea pesticide. A triple quadrupole mass
spectrometer reduces chemical noise for low-level quantitation
in a dirty matrix more than a single quadrupole LC/MS does.
Step 2 This step is accomplished by first selecting the pesticide
of interest at m/z 210 from the co-eluting interferences seen in
the rest of the spectrum. The second spectrum shows the result
after passing through the first quadrupole, or MS1 (Q1).
Figure 18 Multiple reaction monitoring (MRM)